It is dark. You are in the garden, staring down into a big round space surrounded by a wall. On the floor, arranged in a circle, are lots of jars with differing amounts of water. You can barely see them. Thirty people hold their breath. In the centre there is a kind of rod pointing to one of the jars. The pointer lights up, illuminating the first jar. Slowly the pointer starts to move, to rotate towards the next jar, and then the next. It starts to go a little faster. At a certain point, something strikes the jar and makes a soft note, and then another note. It goes faster still; the jars light up and different tones ring out in the night. The light becomes a blur. The music of the water-jars comes alive. Thirty people are watching in silence. It is a miracle.